Datasheet

Section 22 PROM
Rev. 6.00 Mar. 18, 2010 Page 764 of 982
REJ09B0054-0600
• The size of the PROM is 128 kbytes. Always set addresses within the range H'00000 to
H'1FFFF. During programming, write H'FF to unused addresses to avoid verification errors.
22.3.3 Reliability of Programmed Data
An effective way to assure the data retention characteristics of the programmed chips is to bake
them at 150°C, then screen them for data errors. This procedure quickly eliminates chips with
PROM memory cells prone to early failure.
Figure 22.6 shows the recommended screening procedure.
Mount
Programing the chip and
verify programed data
Bake chip for 24 to 48
hours at 125°C to 150°C
with power off
Read and check program
Figure 22.6 Recommended Screening Procedure
If a series of programming errors occurs while the same PROM programmer is being used, stop
programming and check the PROM programmer and socket adapter for defects.
Please inform Renesas Technology of any abnormal conditions noted during or after programming
or in screening of program data after high-temperature baking.